M&K Headers & Active Exhaust Muffler

[RarlyL8]

Our Active Exhaust System for SC & Carrera works so well we decided to build a system for use with headers. Based on the Street version of our Sport Mufflers, this system switches to Sport sound when the engine is under load. Start up and cruise are pleasantly louder than stock, hit the loud peddle and she screams to redline! Bypass tailpipes are adjustable so you can either hide them behind your bumper valance or point them out so they can be seen from behind. We have custom fiberglass valances so you don't have to cut up the OEM unit. Been driving the R&D car around testing the muffler and our new long tube SC headers for a few weeks now and I'm diggin' it! Production version will have the vacuum pots facing back for better ground clearance. Will get some sound clips when time permits.

[Jp-oh]

Art.

[RWebb]

you are really trying to get me to dump my Monty, aren't you?


what's the wt.?

[RarlyL8]

Thanks!
Weight is about 20 pounds due to all the extra features on this muffler. It's still lighter than stock and of course stainless so it will last as long as your 911. I personally am a big fan of the dual purpose that these systems offer. I've got one on all of our R&D cars now. You get a nice bark when you fire up the car and the valves slap shut, a great sound that is not too loud when at idle and cruse, then the gates of hell open when you put your foot in it! Electric controllers can be added that allow the valves to stay open or closed so you have a lot of flexibility. Open the throttle slowly and the valves stay shut, so you could in theory pass the CA sound test.

[freeform911]

Very cool...really wanting to do something with my Carrera...curious if the oil lines need to be changed with the header set up...
Do you have a rough price point for this set up?
TIA
Steve

[75 911s]

Awesome. Best of both worlds. Is it possible to re-route the vacuum lines so they don't hang down?

[RarlyL8]

The Carrera oil line bends upward at the right side cam cover which allows plenty of room for headers. The straight version of that oil line has to be moved up out of the way or the lines need to be back dated.

Production version of the Active Exhaust Muffler will have the vac pots rotated towards the front of the car which will in turn move the vac lines as well for more ground clearance.

Headers and muffler will be priced separately. Muffler will be priced similar to that of our competitor's standard offerings. A LOT of bang for the buck. Long tube headers will be priced similar to our current RSR medium length headers. Plan is for these to be offered in 1.5", 1.63" and 1.75" with or without heat exchangers. They are true equal length with F1 collectors in stainless. All of these will be offered to our host as well along with any updates to the current items. I hope to get a sound clip this weekend and will post up.

[Tony V]

Any reason the muffler couldn’t be used on a 2.7 with ssi’s?

[RarlyL8]

This muffler, as with all of our dual inlet mufflers, can be used on any 911 engine having headers, SSI or early heat exchangers. That is exactly the application it was designed for.

[RarlyL8]

Had a chance to do a quick video today. Method was the same as with the SC/Carrera Active Exhaust video, slow rev to show what it sounds like with the valves closed then a quick rev to hear the valves when open. You can also catch the engine bark real quick when you fire it up. Sorry for the poor focus it was pretty bright out today and I couldn't see the screen very well.

[Jameel]

Brian,

Do you have a video of this setup with the engine under load? I understand the vac pots open up when you punch it, but it's easy to rev quickly with the car just sitting. I'm curious what the vac pots do and how the exhaust sounds in actual sporty driving situations. Thanks!

[RarlyL8]

Sorry don't have any videos driving down the road. The valves remain closed when the engine is not under load, such as idle and cruise (~18"vac). They are full open by 5" vac which allows you to control their operation by modulating the throttle. When the valves are closed the exhaust path goes through both ends and the center section then out the tailpipes. When the valves are open the center section is bypassed and the valves dump the exhaust out the ends. Sound goes from Street to Sport. If you've heard one of our Sport mufflers that is what it sounds like.